Conventionally, to inspect a conduction state or operational characteristics of an inspection target object such as a semiconductor integrated circuit and a liquid crystal panel, a probe unit that accommodates a plurality of contact probes is used for electrically connecting the inspection target object and a signal processing device that outputs an inspection signal. In recent years, with the high integration and the size reduction of semiconductor integrated circuits and liquid crystal panels, a technology applicable to the inspection target object that is highly integrated and reduced in size, by reducing the pitch between the contact probes in probe units has been advanced.
In addition, as the probe unit described above, a probe unit including a contact probe that electrically connects a semiconductor integrated circuit and a circuit board, by bringing both end portions of the contact probe into contact with an electrode of the semiconductor integrated circuit and an electrode of the circuit board that outputs an inspection signal has been disclosed (for example, see Patent Literature 1 and Patent Literature 2).
The contact probe disclosed in Patent Literature 1 includes a first conductive member that comes into contact with an electrode of a semiconductor integrated circuit; a second conductive member that comes into contact with an electrode of a circuit board that outputs an inspection signal; and a conductive coil spring that couples and energizes the first conductive member and the second conductive member. The contact probe disclosed in Patent Literature 2 is cooled from the inside using a tubular-shaped conductive member that is penetrated in the longitudinal direction, thereby preventing the resistance value from increasing.
In addition, a probe unit including a contact probe having a contact unit that comes into contact with an electrode of a semiconductor integrated circuit; and an elastic unit that is coupled to a conducting wire connected to a circuit board for outputting an inspection signal and the like. The elastic unit comes into contact with an end portion at a side different from a side that comes into contact with the semiconductor integrated circuit of the contact unit, has been disclosed (for example, see Patent Literature 3).
Furthermore, a probe unit including a contact probe that comes into contact with an electrode of a semiconductor integrated circuit, and that includes an elastically deformable elastic conductive plate as well as a guide tube that guides an expanding and contracting direction of the elastic conductive plate, has been disclosed (for example, see Patent Literature 4).